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FredBeans 09-16-2010 06:07 PM

Koni Shock/Strut & Epic Engineering Spring Install
12 Attachment(s)
Here is a walkthrough for installing Konis paired with Epic Engineering springs (a FBP exclusive!). This walkthrough is structured based on working with an extra pair of front struts like the ones I bought off this very forum. :) If you don't have an extra set of struts you will need to remove your front struts and break them down which increases the amount of time your car is on jack stands. Either way you will want to plan on a full weekend to do this project at a leisurely pace. Someone who has done it before and has an extra set of cut/painted/prepped Koni fronts would be able to knock this out in a few hours.

Without further ado...

Post #1 - "Cut-a-strut" Installing the Koni shocks into the front struts
Post #2 - Installing springs onto the front struts
Post #3 - Installing springs onto the rear shocks
Post #4 - Installing the complete assemblies into your vehicle
Post #5 - Installed pictures

1. Secure the strut upside down in a vice. Using a punch, mark the center of the strut tube to make drilling easier.

Attachment 226777

2. Use a 3mm or 1/8" drill and drill a pilot hole. Be aware that this tube is pressurized and drilling in this position will cause some fluid to escape in a quick spray. On the two sets I have built this has been very minor, but I would recommend you keep a shop rag handy and wear eye protection.

Attachment 226778

3. Turn the strut over, drain the fluid into a bucket and dispose of it properly. Clamp the strut on it's side and measure down from the top of the strut body according to the directions. I used a scribe tool to mark the strut body in a couple of places at the 40mm mark.

Attachment 226779

Attachment 226780

5. Cut the strut body using a hacksaw and a good blade. The wall of the strut is ~2.5mm thick so you have to be patient and work your way around the strut to get a fairly straight cut. I use a piece of masking tape to help me keep the line.

Attachment 226781

6. When you have completed the cut you can remove the shock insert from the strut body. At this point you will want to go back and remove any heavy burrs from the cut with a file. However, it doesn't need to be perfect as you will be installing a rubber sleeve over the cut (shown later).

Attachment 226782

7. Now you will need to drill out the 1/8" hole on the bottom of the strut body to it's final size. The instructions call for a 14mm (9/16") drill but I was restricted to a 12.7mm (1/2") drill due to the chuck on my cordless drill. This worked fine for me, but your success will depend on how centered you placed the pilot hole to begin with.

Attachment 226783

8. At this point you can either proceed directly to installing the Koni inserts, or you can degrease and paint/powdercoat the strut bodies. I spent ~30 minutes cleaning the struts with turpentine until they were clean, followed that with soapy water and a rinse, and let them dry. Once they were dry I hit them with 3-4 coats of Rustoleum semi-gloss black. You've seen the before pics above... here's the after:

Attachment 226784

9. Now we are ready to install the front Koni inserts. First place the included rubber sleeve over the cut end of the strut body.

Attachment 226785

10. Insert the shock unit into the strut body. Apply a small amount of threadlocker (Loctite 242 or similar) and thread in the bolt/lockwasher/domed-washer in the orientation shown, into the shock through the hole you drilled. Using an 8mm hex key, tighten the bolt. You will feel some resistance as you draw the shock insert into the strut body (assuming you cut it right!). When you bottom out the shock in the strut you will feel it.

Attachment 226786

Attachment 226787

11. Torque the bolt to the required 55 ft*lbs. Repeat for the other side and you are ready to move onto spring installation!

Attachment 226788

FredBeans 09-16-2010 06:08 PM

3 Attachment(s)
12. To assemble the front struts you will need the following hardware:

A) Koni front shock assembled into strut housing
B) OEM dust cover (P/N 20322AG00A, qty.1/side)
C) OEM top mount (P/N
20320AG00A, qty.1/side)
D) Nut & Lock-washer from Koni kit
E) OEM bump stop (P/N
20321AA201, qty.1/side)
F) OEM conical washer (P/N
20326AA000, qty.1/side)
G) OEM upper spring seat (
P/N 20323AG00A, qty.1/side)
H) Epic Engineering front spring

Attachment 226789

13. Install the plastic washer included with the Konis and the push the bump stop onto the shaft of the Koni shock. (Reference pic in step #12)

14. Compress the spring with standard spring compressor tools. Reference step #21 (post #3) for more pictures.

15. Place the dust cover over the strut rod and the spring. Make sure the spring is seated properly in the lower perch.

16. Make sure the strut rod is fully extended and place the upper spring seat onto the strut. If you can not get the spring seat to bottom out on the shoulder of the strut rod you need to compress the spring some more. Also, to make your life easier, you want to make sure that the holes in the upper spring seat are pointed towards the outside of the vehicle (in the same direction as the knuckle bracket at the bottom of the strut.)

Attachment 226790

17. Place the conical washer on top of the upper spring seat, smaller diameter side up. This washer allows the spring seat to interface solely with the inside diameter of the bearing in the strut mount. If you install it upside-down you will essentially be grinding the spring seat/washer/strut mount interface every time you turn.

18. Install the strut mount, studs facing up, and thread the lock-washer and nut onto the strut rod. I use a ratchet to get the nut on as far as possible but only torque it once it's installed on the car. This is what you will have:

Attachment 226791

FredBeans 09-16-2010 06:08 PM

4 Attachment(s)
19. To assemble the rear shocks you will need the following hardware:

A) Koni rear shock
B) OEM dust cover (P/N 20372AE00A, qty.1/side)
C) OEM upper spring seat (P/N 20375AE00A, qty.1/side)
D) Nut & Lock-washer from Koni kit
E) OEM top mount (P/N 20370AG00A, qty.1/side)
F) Epic Engineering rear spring
G) Lower spring perch from Koni kit

20. Install the lower spring seat onto the shock. It is common for people to install this upside down, so make sure the seat is oriented as in the picture below. Go ahead and install the dust cover while you are at it. The rear dust cover needs to be "forced" onto it's mounting boss on the shock as it is a very tight fit.

Attachment 226792

21. Compress the spring with standard spring compressor tools. Install the spring with the spring seat, top mount and hardware. The upper spring seat should be oriented as shown in the picture. *NOTE* Rotate the top mount so that the studs are perpendicular to the lower bolt axis before. The picture below does not represent this.

Attachment 226793

Attachment 226795

22. Tighten the nut and lock-washer with a ratchet. Remove the spring compressors. Save the final torquing for once it is installed in the car. You now have this:

Attachment 226794

FredBeans 09-16-2010 06:09 PM

4 Attachment(s)
23. Break the lug nuts slightly loose on the front wheels. Jack up the front of the car and lower onto jack stands. After making sure the car is stable, remove the front wheels.

24. Using a 12mm socket remove the bolts that secure the ABS wheel speed sensor line and brake line to the strut (circled in red below). Move them out of the way, you will want to make sure you don't pull, bend or otherwise stress them unnecessarily.

Attachment 226796

25. Using a wrench on one side and a ratchet (or impact) on the other side, remove the cam adjusting bolt and lower mounting bolt from the strut/knuckle interface (circled in yellow above). At this point the control arm and knuckle/spindle will sag. You can support it with a jack stand, block of wood, etc., or you can let it hang.

26. Open the hood and locate the three nuts that hold each strut mount to the strut tower, near the firewall (shown below). Have a helper loosen the nuts while you hold the strut. After the third nut is removed the strut will want to drop. Carefully navigate the strut out of the wheel well, avoiding the ABS and brake line as well as the CV boot.

27. Install your assembled strut in the reverse order of removal. Make sure to double check that the drain holes in the upper mount are facing toward the outside of the vehicle. When installing the cam adjusting bolt you will want to try and get as much negative camber as possible. I do this by turning the bolt and watching the brake rotor. Once the rotor is as tipped in at the top as it can get, I torque down the nut. By doing this on both sides I get reasonably even camber which will do until I get the car to the alignment shop. Here is a pic of the installed assembly followed by the torque specs for the OEM bolts.

Attachment 226797

Attachment 226798

28. When the wheels have been reinstalled, the car lowered and the lugs torqued, you can now torque the nut at the top of the strut rod. Koni recommends you use a pass-thru wrench to torque the nut while you hold the strut rod via the hex feature at the top of the shaft. I have never felt very comfortable doing it this way but fortunately the strut rod won't spin when the weight of the vehicle is on it. Simply torque the nut using a deep socket to the 37 ft*lbs as called for in the Koni instructions.

29. Onto the rear shocks... raise the rear of the car and remove the wheels like we did for the front.

30. Use your floor jack to compress the rear suspension slightly by jacking at the bottom of the shock (reference pic for next step). Basically we are trying to take the load off the bolt that connects the shock to the trailing arm. If you haven't soaked that bolt and nut in P'Blaster or Liquid Wrench, now is the time.

31. Here is where you will really appreciate your impact wrench. My favorite method for removing this tricky bolt is to put the impact on the inside (bolt head) and a breaker bar on the outside (nut). Have your helper hold the breaker bar, against the ground if possible, and let 'er rip with the impact. My Milwaukee 300 ft*lb electric makes quick work of this nut/bolt and anti-seizing during reassembly will make it a breeze the next time. If you are lucky it will come right apart and then you can pull out the bolt or give it a few taps with a hammer to extract it. Once this is done you can release the floor jack and let the shock extend fully.

Attachment 226799

32. Open the trunk and remove the floor liner. Crawl inside and roll up the liner at the back corners of the trunk. This will expose the tops of your rear shocks. With a friend holding the shock, remove the two nuts and let the shock drop from the car.

33. Install your assembled Koni shock in reverse order of removal. When ready, reinstall the wheels and lower the vehicle. Similar to the installation of the fronts, once the car is back on the ground you will go in and torque the top of the shock rod (37 ft*lbs).

Attachment 226800

Attachment 226801

34. At this point you will want to review the procedure and make sure you didn't over look any steps, torquing any fasteners, etc. I used the knob included with the Konis to set all corners to 1-turn, starting from full-soft. This is right in the center of their range and so far I have not felt the need to change it.

That's it! Take the car out for a test drive to make sure everything is working properly. You may get a few clunks and creaks as things settle in, but as long as the car behaves properly you should not worry about it. After a few days these sounds will go away.

To really get the benefit of these components you will want to take the car in for an alignment as soon as possible. I like to get as much negative camber from the front as possible (and even side-to-side), about .5 degrees less camber in the rear, and zero toe all around. This makes for great grip at street levels, very little tire wear, and a good starting point for tweaking things like swaybars, front/rear damping stiffness, tire pressures, etc.

FredBeans 09-26-2010 01:41 PM

Konis + Epic Engineering Springs
Rota Tarmac II, 18x7.5 e48 wrapped in Toyo T1-R's 225/40-18

FredBeans 09-29-2010 06:29 AM

Nice write up Rick! :)

mustangendsley 09-30-2010 10:50 AM

should i get some spec b top hats for this also? do you need spacers for the saggy butt?

FJuan 10-01-2010 11:54 AM

Very nice write-up indeed. Thank you.

m sprank 10-02-2010 12:10 PM

To make the install even easier, not have to measure, and not use a hacksaw...

Get a pipe cutter.

Home Depot:
Brand: BrassCraft
Part Number: T005
Cutting: 5/8 to 2 1/8" OD

Brand: SuperiorTool
Part Number: ST-2000
Cutting: 5/8 to 2 1/8" OD

I love clean, straight cuts. Easier, no sore arms, quicker, safer, perfect every time.

I used the Lowes one last time. My Rigid is overkill. But both the Lowes and HD work. Ask me how I know.

Just checked The BrassCraft is $22.98. Spend $25 and do it like a Pro. You still have the tool for other projects later.

Set the blade of the cutter as close to the top of the strut as possible. The blade sits between the frame, so one side of the tool frame will rest against the silver edge of the strut top. The blade will be a hair below on the black body. The silver edge will guide the tool in a perfect straight line. The cut will be clean, just de-burr the inside. It will also be at the perfect height. No measuring required.

Work smarter, not harder.

Great write up Rick.

toreadorranger 10-04-2010 07:21 AM

x2 on the pipe cutter. Makes it real easy.

ToRealEyes 10-18-2010 12:19 PM

To go along with this combo, is it recommended to also install either/or/and:

1. Whiteline Steering Rack Bushing Kit
2. Whiteline Roll-Center & Bump-Steer Complete Kit
3. others? ie. to compensate for (lowered) frame geometry

mustangendsley 10-18-2010 12:37 PM

I probable would do the Roll-center and Bump-Steer kit in due to the ball joint very hard to get off. I have herd that once you replace it it is very easy to get off.

m sprank 10-18-2010 02:39 PM

^ Huh?

ToRealEyes 10-18-2010 04:01 PM

huh to the question? I remembered reading somewhere that the lowered stance messes with the frame response dynamics in handling and bump dampening. I can't remember which part it is..

BoozeRS05 10-18-2010 04:11 PM

Now that's a write-up.

Glad mine were assembled for me, altho that doesn't seem too bad.

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